Deflecting means for a doubling plate in a textile drafting apparatus



Oct. 8, 1963 J. K. P. MACKIE 3,105,997 DEFLECTING MEANS FOR A DOUBLING PLATE IN A TEXTILE DRAFTING APPARATUS Filed Feb. 5, 1962 Inventor M W W,-

United States Patent 3,105,997 DEFLECTHIG MEANS FOR A DOUELIPJG PLATE IN A TEXTHE DRAFTlNG APPARATUS John Kay Pringie Maclde, Belfast, Northern Ireland, as-

signor to James Mackie & Sons Limited, Belfast, Northern Ireland, a British company I Fiied Feb. 5, 1962, Ser. No. 170,920 Claims priority, application Great Britain Feb. 2%, 1961 7 Claims. (Cl. 19-243) This invention relates to machines for drafting textile slivers in which mechanism is provided for the automatic variation of the draft on the machine corresponding to the weight or thickness of the sliver being fed and is particularly concerned with such machines for the treatment of jute and other hast or leaf fibres.

The general principle of automatic draft control is well known and for this purpose thethickness of sliver enter ing a drawing frame or other form of drawing head is measured by a pair of measuring rollers and after a time delay corresponding to the interval during which the sliver in question is passing from the measuring rollers to the drafting Zone, the draft of the machine is adjusted in accordance with the thickness of the sliver, being increased for a sliver which is thicker than average and reduced for a sliver which is thinner than average.

When such a machine is used, for example for the treatment of wool or synthetic fibres, only a single pair of measuring rollers is necessary. The fibres are all condensed together to pass between the measuring rollers and are then opened out again to pass to the drafting zone. The natural bulk and resilience of such fibres renders this relatively simple. In the case of jute, flax and similar fibres, however, this is not possible as the fibres have no equivalent resilience and when drafting a number of parallel slivers it is, therefore, necessary to use several pairs of measuring rollers, for example one pair for each individual sliver.

In order to operate the automatic draft control mechanism, it is necessary to include an averaging device so that the draft at any instant corresponds to the average of the thicknesses of the slivers passing the measuring rollers a short interval previously. After drafting the individual slivers require to be doubled and this operation produces a relative displacement between the individual slivers. The reason for this is that the standard form of doubling plate allows one sliver (normally that at one of the edges) to-pass straight through but causes all the other slivers to pass round two right-angled bends so as to align them with the first sliver with which they are amalgamated as they pass through the delivery rollers. Thus, each of the other slivers passes firstly through a slot in the doubling plate which is inclined at approximately 45 to the direction of travel of the sliver. This deflects the sliver through 90 and it then travels at right angles to its previous path until it reaches the line of the first sliver when it passes through a further 45 slot which turns it through a further right-angle and restores it to its original direction of motion but displaced sideways so as to be in alignment with the first sliver.

It is this additional path which all but one of the slivers have to follow that produces the relative displacement referred to above. Since there are inevitable variations from sliver to sliver, and since the draft control mech- 3,105,997 Patented Oct. 8, 1963 anism operates in accordance with the average thickness, the thickness of the composite body of slivers after doubling is only regulated as long as the points at which the measuring rollers have operated at any one time are in register with one another. The relative displacement caused by doubling, therefore, inevitably introduces a degree of irregularity in the doubled sliver.

According to the present invention members are provided between the drafting rollers and the doubling plate to define paths for the individual slivers, these paths different in length in such a way that each sliver travels approximately the same distance between the drafting rollers and the delivery rollers. This compensates for the relative displacements brought about by the doubling plate and thus maintains the regularity of the emerging sliver while still retaining the effective operation of the standard form of doubling plate.

There is a further problem involved in the use of a gill drawing head in that when the slivers have passed through a gill bed, there is an additional source of shortterm irregularity in the sliver. This is caused by the periodic withdrawal of the pins on the fallers and is known as faller marking, the distance between these irregulari ties being known as faller period. The faller period is the product of the pitch of faller and the draft of the machine and in a typical case using a /2" faller pitch and a draft of 5, the faller period is 2 /2". The relative displacement of individual slivers during doubling'has the valuable effect of dispersing the faller marking in the doubled sliver and consequently of virtually eliminating it. As already mentioned, however, this relative displacement inevitably introduces a degree of irregularity in the doubled sliver and in fact to a large extent destroys the effect of the automatic draft control.

Preferably, therefore, the total distances travelled by individual slivers between the drafting rollers and the delivery rollers'differ from one another by a proportion of the faller period when the machine is operating atrits standard mean draft, so as to achieve a small relative lengthwise displacement of the slivers sufficient to disperse the faller marking. In other words, from the point of view of the automatic draft control the compensation is sufliciently complete as to avoid affecting the long-term regularity of the sliver while at the same time the fact that there is a slight difference in the distances travelled by the individual slivers ensures that the faller marking is distributed substantially. uniformly over the whole "of each faller period. I

Most simply, the paths of the slivers are such that the sliver which suffers the greatest deflection by the doubling plate follows its normal path andis not deflected further while the paths of the other slivers are lengthened accordingly; These paths may be lengthened in a vertical direction by the provision adjacent the drafting rollers of members at the appropriate heights for the individual slivers so that each sliver passes upwardly'in contact with the surface of the drafting pressing roller, over its member, and then downwardly again and round a further roller before reaching the doubling plate.

A construction in accordance with the invention will now be described in more detail by way of examplewith reference to the accompanying drawings, in which:

FIGURE 1 is a digarammatic side view of the apparatus; and

FIGURE 2 is a perspective view from the front showing the relationship between the drafting rollers, the doubling plate and the delivery rollers.

FIGURE 1 does not show the automatic draft control arrangement itself but this is controlled by measuring rollers 1 cooperating with feed rollers 2 for each sliver. The feed rollers 2 turn about fixed bearings and the measuring rollers 1 are pressed downwardly to an extent depending on the thickness of the sliver. The average of the deflection of the rollers 1 is derived mechanically and the draft applied to the machine is adjusted accordingly. The sliver shown as 3 accordingly passes between the rollers 1 and 2, over a jockey roller 4, beneath a further feed roller 5 and thence to the drafting zone indicated generally at 6. The slivers are drafted by means of a drafting roller 7 and an associated pressing roller 8 in the usual way, after which they pass to a doubling plate 9 of the normal construction as seen in more detail in FIGURE 2.

In FIGURE 2 the individual slivers are shown as 3a, 3b, 3c and 3d and it will be seen that the sliver 3a is not deflected in any way by the doubling plate but merely passes. through in a straight line from its point of issue from the nip. of the drafting rollers. The sliver 312, however,passes downwardly through a diagonal slot 12 which is inclined at 45 to the line of the sliver. The sliver accordingly then passes beneath the doubling plate at right angles to its original direction of motion and then up through a further diagonal slot 13 from where it travels immediately beneath the sliver 3a to the delivery rollers 16 in the usual way. Similarly sliver 30 passes downward-1y through a diagonal slot 14 and then up again through the slot 13. The sliver 3d passes downwardly through a diagonal slot 15 and also up through the slot 13. As a result all four slivers are superimposed as they pass to the delivery rollers where they are combined together by the pressure of the rollers.

With the normal arrangement of doubling plate each sliver passes directly from the nip of the drafting rollers to its diagonal slot (apart from the sliver 3a which is not acted on by the doubling plate). As a result of this the sliver 3b travels a distance greater than the sliver 34 equal to the distance between the slots 12 and 13 and the slivers 3c and 3d also travel correspondingly greater distances. It is this relative displacement of the slivers which leads to the irregularity of the combined sliver referred to in detail above. I

In accordance with the present invention, however, the paths of the various slivers between the drafting rollers and the delivery rollers are so adjusted as to make the total distances traveled approximately equal. For this purpose, the paths of the slivers 3a, 3b and 3c are all extended in an upward direction while the path of the sliver 3d (which is the longest of the four paths) is not modified. Thus, the sliver 3a passes upwardly in contact with the surface of the drafting pressing roller 8, over a small rod 20 and then down again and beneath a further driven roller 21. Similarly, the sliver 3b plasses up and over a small rod 22 mounted on a lower level than the rod 20 and from there down and beneath the common roller 21 before passing to the slot 12 the doubling plate. The sliver 30 passes over a small rod 23 which is again mounted on a lower level than the rod 22 and again under the common roller 21 before passing to the slot 14 of the doubling plate. The provision of a drive to the roller 21 avoids excessive tension in the slivers when starting the machine. Guide plates shown as 25 and 26 extend between each rod 20, 22 and 23, to facilitate the threading of the slivers.

The heights of the additional rods 20, 22 and 23 are such as to extend the path lengths of the various slivers so as to make the total distances travelled approximately equal asv stated above. In order to overcome the additional problem of father marking, already discussed,

the total distances travelled are not made precisely equal but differ from one another by a proportion of the faller period when the machine is operating at its standard mean draft. Ideally when four slivers are to be doubled together as shown, each total distance should differ from the next by an amount equal to one quarter of the faller period.

In order to permit the rods 20, 22 and 23 to be located with accuracy each is supported by an individual bar 27, 28 and 29 seen in FIGURE 1 but not in FIGURE 2. These bars are screwed by their lower ends 30 into an extension of the doubling plate 9 and this screwed con nection permits the required axial adjustment of the bars to adjust the relative path lengths of the slivers.

After the upward deflection of the three slivers 3a, 3b

and 3c, they pass to the doubling plate 9 as already described and the action of this plate is to bring the four slivers into line in the usual way so that they pass to the delivery rollers together. In other words, theonly substantial modification to the normal arrangement is the fitting of the rollers 20, 21, 22 and 23 which provide the relative adjustment of the path length. By means of such adjustment, however, the full benefits of automatic draft control in providing a very even sliver are obtained while at the same time overcoming the difliculties of faller marking.

I claim:

1. In drafting apparatus for the treatment of a plurality of parallel textile slivers, said apparatus including mechanism for the automatic control of the draft in accordance with the average thickness of said slivers when entering said apparatus, drafting rollers and delivery rollers, the novel combination which comprises: a doubling plate for the drafted slivers arranged intermediate said drafting rollers :and said delivery rollers whereby said slivers are superimposed before passing to said delivery rollers and all but one of said slivers are deflected in an increasing manner; and members mounted between said drafting rollers and said doubling plate, said members defining inversely increasing paths for all but said one of said slivers, said paths diiiering in length in such a way that each sliver travels approximately the same distance between said drafting rollers and said delivery rollers.

2. Apparatus according to claim 1 in which said mem: bers are so located that the total distances travelled by individual slivers between said drafting rollers and said delivery rollers, differ from one another by a proportion of the taller period when the machine is operating at its standard mean draft, so as to achieve a small relative lengthwise displacement of the slivers sufiicient to disperse the faller marking.

3. Apparatus according to claim 1 in which said one sliver is fed directly to said doubling plate from the drafting rollers. i

4. Apparatus according to claim 1, in which said members :are located adjacent and above said drafting rollers at the different heights for the individual slivers and including a further roller located in contact with all of said slivers between said members and said doubling plate whereby the paths of all but said one of said slivers are lengthened in a vertical direction.

5. In drafting apparatus for thet-reatment of a plurality of parallel textile slivers, said apparatus including mechanismfor the automatic control of the draft in accordance with the average thickness of said slivers when entering said apparatus, drafting rollers and delivery rollers, the novel combination which comprises: a doubling plate for the drafted slivers arranged intermediate saiddrafting rollers and said delivery rollers; a plurality of members mounted adjacent and above the level of slivers emerging from said drafting rollers; a further roller mounted adjacent said doubling plate in contact with all of said slivers, saidmembers and said further roller de-. fining paths for said slivers between said drafting rollers and said doubling plate, said paths being elongated in an upwards direction for all "but one of said slivers and differing in length in such a way that each sliver travels approximately the same distance between said drafting rollers and said delivery rollers.

6. Appanatus according to claim 5, in which said further roller is positively driven.

7. Apparatus according to claim 5 and including means for adjusting said members in a vertical direction.

6 References Cited in the file of this patent UNITED STATES PATENTS 277,606 Prest May 15, 1883 FOREIGN PATENTS 463,447 Great Britain Mar. 31, 1937 493,148 Great Britain Jan. 4, i939 

5. IN DRAFTING APPARATUS FOR THE TREATMENT OF A PLURALITY OF PARALLEL TEXTILE SILVERS, SAID APPARATUS INCLUDING MECHANISM FOR THE AUTOMATIC CONTROL OF THE DRAFT IN ACCORDANCE WITH THE AVERAGE THICKNESS OF SAID SILVERS WHEN ENTERING SAID APPARATUS, DRAFTING ROLLERS AND DELIVERY ROLLERS, THE NOVEL COMBINATION WHICH COMPRISIES: A DOUBLING PLATE FOR THE DRAFTED SILVERS ARRANGED INTERMEDIATE SAID DRAFTING ROLLERS AND SAID DELIVERY ROLLERS; A PLURALITY OF MEMBERS MOUNTED ADJACENT AND ABOVE THE LEVEL OF SILVERS EMERGING FROM SAID DRAFTING ROLLER; A FURTHER ROLLER MOUNTED ADJACENT SAID DOUBLING PLATE IN CONTACT WITH ALL OF SAID SILVERS, SAID MEMBERS AND SAID FURTHER ROLLER DEFINING PATHS FOR SAID SILVERS BETWEEN SAID DRAFTING ROLLERS AND SAID DOUBLING PLATE, SAID PATHS BEING ELONGATED IN AN UPWARDS DIRECTION FOR ALL BUT ONE OF SAID SILVERS AND DIFFERING IN LENGTH IN SUCH A WAY THAT EACH SILVER TRAVELS APPROXIMATELY THE SAME DISTANCE BETWEEN SAID DRAFTING ROLLERS AND SAID DELIVERY ROLLERS. 